Search Unified Audit Log

 $data = Search-UnifiedAuditLog 
         -StartDate $startInterval 
         -EndDate $endInterval 
         -Operations FileAccessed, FilePreviewed, PageViewed, PageViewedExtended, SearchViewed, CompanyLinkUsed, SecureLinkUsed, FileDownloaded, FileModified, FileUploaded, FileDeleted, FolderModified, CompanyLinkCreated, SharingInheritanceBroken, ListUpdated, FileSyncDownloadedFull, FileSyncUploadedFull  
         -SessionId $sessionId 
         -SessionCommand ReturnLargeSet 
         -ResultSize 5000
 ## Start Date - Date and Time in local Computer Date Time format
 ## End Date - Date and Time in local Computer Date Time format
 ## Operations - For more information see here - https://docs.microsoft.com/en-gb/office365/securitycompliance/search-the-audit-log-in-security-and-compliance#sharing-and-access-request-activities 
 ## Session Id - Essential for paging and handling when data goes more than threshold limit
 ## Session Command - Determines the size of the data returned
 ## ResultSize - 5000 seems to be the upper limit for a successfull data pull